P5MCFF1 Separating wall and roof with insulation at rafter level

Build Up

Party Masonry Cavity Wall

Separating Wall and Roof

2 x Leaves Lightweight Blockwork Party (Separating) Wall

Cavity fully filled with insulation

150mm insulation (λ = 0.044W/mK) between the rafters

50mm (λ =0.022W/mK) below the rafters

This LABC Registered Construction Detail is only valid for use with building work intended to follow the guidance in the following:

England

• Approved Document L1A and L2A (2013 edition incorporating amendments up to and including 2016)
• Approved Document L1B (2010 edition incorporating amendments up to and including 2018)
• Approved Document L2B (2010 edition incorporating amendments up to and including 2016)

NOTE: This LABC Registered Construction Detail should not be used for Approved Document L Volume 1 and 2 (2021 edition) or any subsequent amendments.

Wales

• Approved Document L1A, L1B, L2A and L2B (2014 edition incorporating amendments up to and including 2016)

NOTE: This LABC Registered Construction Detail should not be used for Approved Document L Volume 1 and 2 (2022 edition) or any subsequent amendments.